Annealing-furnace.



J. A. SWINDELL.

ANNBALING FURNACE.

APPLIGAMON FILED 1920.12, 1913.

1 1 1 2,236, Patented Sept. 29, 1914.

' 4 SHBETS-SHEET 1.

2 I l. lz

INVENTOR @1... @tm MMU RS Ca.. PHOTO-LITHO.. WASHINGTON, D. C.

4 SHEETS-SHEET 2.

Patented Sept. 29, 1914.

J. A. SWINDELL.

ANNBALING PURNAGE.

APPLIGATION FILED DBO. 12, 1913.

J. A. SWINDELL..

ANNEALING FURNAGB.

APPLICATION FILED DE0.12,1913.

Patented Sept. 29, 1914.

4 SHEETS-SHEET a.

WITNESSES Patented Sept. 29, 1914. 4 SHEETS-SHEET 4.

THE MORRIS PETERS Co., PHOTOYLITHO.. WASHING rON. D. C

eiirrnn sra'riis PATENT oFFicE.

JUHN .ALBERT SWNDELL, PITTSBURGH, PENNSYLVANIA.

ANNEALING-FURNACE.

To all 1071.07.17, tt may concern Be it known that l, JoHN ALBERT SWIN-DiiLL, a citizen of the United States, residing at Pittsburgh, in thecounty of Allegheny and State Pennsylvania, have invented a new anduseful lmprovement in jinnealingl'lurnaces, of Which the following is afull, clear, and exact description,'reference be*- ing had to theaccompanying drawings, forming part of tliisspeciiicationdn Which--Figure l is a transverse vertical section of one form of annealing`furnace embodying my invention. 2 is a section on the irregular lineH-ll of lig. 1. Figs. and 4 are vertical sections showing two otherforms of the invention. Fig. 4aL is a detail sectional vieiv showinganother form. 5 is a sectional perspective view showing still anotherforni. Fig. 6 is a vertical section showing a fifth form of myinvention. Fig. 7 is a section on the `irregular line vllt-Vfl' of Fig.6, and Fig. 8 is a vieiv similar to Fig. 7 showing a still furthermodification.

My invention has relation to annealing` furnaces and more particularlyto furnaces of the class which are designed to receive and impart heatto annealing boxes contain-v ing sheets, plates or other to be annealed.

The invention is especially designed as an improvement upon the furnacedescribed and claimed in the patent to iVVillia i A.

mi J. o. smeden, ive. estasi @i May 2,1

1899. he furnaces of that patent have been highly successful inpractical operation and have gone into Wide use, particularly in the artof annealing` sheets and plates.

The present invention is designed to still further increase theefficiency of the furnaces of the said patent. l

With this object in view the invention consists mainly in therearrangement ofthe gas, air and ivaste port-s of the furnace in suoli amanner that the produ cts of combustion enter the annealing chamber ofthe furnace at its central portion (or in the case of a divided furnace,adjacent to the inner wall of each annealing compartment) and thencepass upwardly in parallel over the annealing boxes and thence'downwardly` through escape ports adjacent to the outer side Walls of theannealing chamber or comH pertinent. These outer side ivallsbeing'directly exposed to the atmosphere are subject to loss of heat and thereis, therefore, a tend- Speciiicatoii. of Letters Patent.

Application. filed December 12, 1913.

articles which are w furnace is provided With the `doors 6 at one end.4

Patented sept. 29, 1914.

Serial No. 806,224.

ency for the outer portions of the boxes to be at a somewhat lowertemperature than the inner portions.

By my invention, the products of combustion, which are still at a hightemperature, are continually impinged directly against these outerWalls, thereby maintaining them at a high temperature.

rlhe invention further consists in so arranging the air, gas and Wasteiues as to retain the advantages possessed by the furnaces of thesaidpatent.

I also provide simple and efficient means for regulating the temperatureof different portions of the furnace by the admission of relatively coldair from the outside, but in such a manner as to avoid `undue coolingdoivn of the annealing chamber or compartment.

In the accompanying drawings I have illustrated several different`constructions of furnaces embodying my invention.

Referring first to that form shown in Figs. 1 and 2, the numeral 2designates the side Walls of thefurnace, 3 the roof and 4 the base. 5designatesthe `annealing chamber, Which is of double forni, beingdesigned to support aroW of annealing boxes placed end to end at eachside of the center. The usual charging The numeral 7 designates tWo gasinlet flues, one at each sideof the central dividing Wall 8 and theseflues enter the "furnace at one end and extend in a parallel.longitudinal direction. upper portion a series of ports 9 leading.Iupvvardly at opposite sides of the central Wall 8. This Wall 8 ispreferablyextended upivardly somewhat above the level of theboxsupporting portionsilO of the floor ofthe chamber 5, and may, ifdesired, be extended to any distance even entirely to the roof; thusdividing said chamber into tivo com* partments, as indicated in fulllines in Fig. o. The outer Walls 11 of the ports 9 are also preferablyextended upwardly so as to direct the products of combustion upwardlyinto the annealing chamber.

12 designatesthe air inlet iues, one at each side of the furnace,` andeach of them f having a plurality of ports 13 leading from their upperVportion and communicating with the gas ports 9. The waste {iues of thefurnace each have tWo passes 14 and 14a.

Each of theseiues has at its cate with the annealing chamber 5 by meansof a plurality of vertical ports 15 through which the waste gasesdescend at opposite sides of the said chamber. .lhe passes 1e of thesewaste iiues are located at each side intermediate the adjacent air andgas iues, the two passes being connected at 141.

16 designates damper briclrs which are adapted to extend throughopenings in the side walls 2 of the furnace a short distance below theupper ends of the ports 15. rthese damper bricks are arranged to fitsomewhat looselyin these openings and can be adjusted therein so as toregulate the draft. They provide means by their eect upon the draftwhereby the heat at different portions along the length of the annealingchamber can be regulated as may be desired. any cold air admitted tothese points does not directly enter the annealing chamber, but passesdown into the waste ues, and therefore does not chill the temperature insaid chamber.

It will be noted that all the flues extend in parallel longitudinalrelation, being similar in this respect to the furnace of the Swindellpatent above referred to. This is a feature of very great importance inpractice, since the dividing walls between the several flues are alsolongitudinally arranged and are thus much less liable to injury in theoperation of the furnace. rlhat is tosay, these walls extend in the samedirection as the movement of the boxes into and out of the furnace.These boxes and their contents are of great weight and the total load onthe furnace floor is frequently very large. ThisY parallel longitudinalarrangement: of these dividing walls provides a supporting base ofmaximum strength. ln these figures have shown the inlets 12a for thelongitudinal air lines 12 as communicating with said fiues centrally oftheir length, the air spreading and flowing longitudinally in bothdirections and thence through the ports 13. It will also be noted thatby the arrangement of flues described7 l obtain the advantages ofpreheating the air, which is a feature of the said Swindell patent.These furnaces are kept in a highly heated condition for relatively longperiods. The entire base of the furnace, therefore, becomes very highlyheated, not only by conduction through the floor of the annealingchamber, but also by conduction through the walls separating the wastefines from the air and gas flues.r The resultis that both the air andVgas are preheated to a very considerable degreebefore reaching thepoints of combustion. This e'ects a considerable saving in fuelvandutilizes heat which would otherwise be losteither by conductionthrough the base of the furnace into the foundation or b v passing ofithrough the stack. l have found that .this preheating, through the wallsof the waste fines, will take place to a beneficial extent even wherethese walls are of very considerable thickness owing to the high degreeto which the furnace becomes heated in operation.

In the modification shown in Fig. 3, the construction is substantiallythe same as that just described, but the waste `llues 1T are single passfines instead of double pass.

ln the modification shown in Fig. 4f, the construction is the same usthat shown in Fig. 3, .xcept that instead of a single pass air flue ateach side, Yi provide cach air flue with double passes 18 and 15). llhiseffects a further preheating of the air. 'lhis forni also differs fromFig. 3 in having a single central gas fine 20 which eonnminicates withthe air ports 21 from the air fines 19 by means of the vertical ports22. ln this form he central wall 8 is not present.

The construction illustrated in Fig. la is similar to that shown in F4f, but diliiers therefrom in that the ports 2Q are staggered, oralternate, with relation to the ports 21.

ln the construction shown in F ig. 5, Q3 and E23a designate the doublepass waste fines similar to those shown in Fig. 1. E24 designates theair fiues and 25 the single central gas flue. Each air flue Q4 has aseries of oblique transverse ports ZG leading from its upper portioninto a chamber 27 formed by the hollow central wall 9.3. The gas flue 25has two sets of vertical ports 29 and 30. rilhe ports lead upwardly atone portion of the wall 28, while the ports 30 lead upwardly at theopposite side of said wall, being shown in dotted liucs in this ligure.The gas and air ports are staggered so that at each side the gas and airports alternate. rllhe gas escapes from the ports Q9 at the upper edgesof the balile walls 31, while the air escapes adjacent to these pointsthrough openings 32 in the upper portion of the hollow wall 28.

ln the form shown in Figs. (S and 7, the waste flues 33 are single passiiues, while the air flues 34 and 3i are double pass flues. 35 is acentral gas fiue. ln this form the chamber 36 within the central hollowwall 37 forms an initial combustion chamber with which the passes 34eaof the air flucs communicate by means of the ports 3S and with which thegas fine communicates by vertical ports 39. The products of combustionescape through the side openings L l-O in said central wall. Theconstruction shown in Fig. 3 is similar to that shown in Figs. (i andi', but instead of the air fiues each malring two complete passes. eachair flue consists of an inlet portion l-l which extends to about thecenter of the furnace where it communicates with the main air flue 42from which the air flows in beth directions.

The specific construction shown in Figs. 5,

rlhe constructions 6 and 7, are the joint invention `of John C. Swindelland myself and form the subject matter of a co-pending jointapplication. These figures are illustrated and described herein,however, as showing specific embodi-4 ments which the broader inventionherein claimed may take.

1t will be noted that all the forms of the invention described possessthe advantages of the longitudinal iiue arrangement before described andalso to a greater or less extent the advantages of air or air and gaspreheating. In all the forms, the combus tion originates at or near thecentral portion of the furnace, and the products of combustion pass inopposite directions over the annealing boxes toward the outer sidewalls.

provide for a high degree of uniformity in heating, not onlyas to allthe boxes, but as to different `portions of the same box. The wasteoutlets being at the outer sides of the furnace not only maintain theseside walls at a high temperature, but in chilling, action which `thcWalls would exert upon the gases is exerted upon outgoing Waste gasesafter they have passed the boxes. It will also be noted that either sideof the furnace can be worked to a large extent independently of theother side. It frequently happens that a different charac` ter ofmaterial is being treated in one side of the furnace than in the other,and requiring either a different temperature, or treatment for adifferent length of time. In furnaces constructed in accordance with myinvention this can be readily done since the heat conditions at the twosides can be sep` arately regulated. v

The invention is subject to other modiiications than those hereindescribed without departing from the spirit and scope' of the appendedclaims.

While my invention has been more specifically designed for use inannealing furnaces, it is obvious that it is applicable to other heatingfurnaces.

What l. claim is:

l. A furnace of the character described, comprising a heating chamber orcompartment for the articles to be heated, having an inlet port for theheating medium opening into the inner side of said chamber orcompartment, and an outlet port for the waste gases leading from theouter side of said chamber or compartment, the base of the furnace belowsaid chamber or compartment having` longitudinally arranged air, gas andwaste flues, the waste iiues having portions which are below the outerside portion of the said chamber or compartment, and the gas iue beingbelow the inner side of said chamber or compartment, the air and gasflues having ports which connect the iiues with said inlet port, and thesaid being connected to the outlet-port being connected to the said wasflue; substantially as described.' i

2. A furnace of the. character described, having a `heating :chamber orcompartment for the articles havinginlets extending along and openinginto its `inner side portion, and also `having outlets extending along'andopening .from its outer sidey portion, f with a supporting floor forthe articles to be heated between the said `inlets and` outlets, thebase of the `furnace having longitudinallyarranged air,

gas and waste flues therein, with ports leading from the air and gasflues and communito `be heated, said chamber eating` with said inlets,and other ports comf municating with said outlets and leading to thewaste flue; substantially as described.

3'. A furnace of comprising a heating chamber or compartment for thearticles tobe heated, having an inlet port for the heating mediumopening into the inner side of said chamber or compartment, and anoutlet port for the waste gases leading from the outer side of saidchamber or compartment, the base of the furnace below said chamber orcompartment having longitudinally arranged air, gas and waste lues, thewaste lues having portions which are below the outer side portion of thesaid chamber or col'npa'rtment, and the gas Hue beingbelow the innerside of said chamber or compartment, the air and gas lues having portswhich connect the flues with said inlet port, and the said outlet portbeing connected to the said waste flue, some of said iiues having doublepasses; substantially as described.

4. `A furnace of the character described, comprising a heating chamberor compartment for the articles inlet port for the heating mediumopening intothe inner side of said chamber or compartment, `andanioutlet port for the `waste gases leading from the outer side of saidthe'character described,

to be heated, having an chamber or compartment, the base of the lfurnacebelow said chamber or compartment `having longitudinally arranged air,gas and waste iiues, the waste flues having portions which are below theouter side portion of the said chamber or compartment, andthe gas fluebeing below the inner side of said chamber or compartment, the air andgas iues having ports which connect `the fiues with said inlet port, andthe said outlet port said waste flue, some of said lues havingdoublepasses in substantially the same horizontal plane; sub-` stantially asdescribed.` i

5. A furnace of the character described, comprising aheating chamber orcompartment for the articles to be heated, having an inlet port for "theheating medium `opening into the inner side? of said chamber orcompartment, and an outlet port for the Wastegases leading. from theouter side of said chamber or compartment, the base of ,the furnacebelow said chamber or compartnient having longitudinally arranged air,gas and waste flues, the waste` fines having portions which` are belowthe outer side portion of the said chamber or compartment, and the gasflue being below the inner side ofsaidA chamber or compartment, the airand gas fines having ports which connect the flues with said inlet port,and the said outlet port being connected to theI said waste flue,together with damper means for the ports which connect the outlet withthe waste fines; substantially as-described.

6.*A furnace of` the character described having an annealing chamberprovided with waste-port connections adjacent to its outer side walls,andwith twosets of inlet port connections adjacent its center, and alsohavingmeans for supporting articles to be annealed at each side of thecenter between the inlet and outlet connections, the base of the furnacebelow said chamber having longitudinally arranged air and gas fluestherein with which the said inlet port connections communicate, and alsohaving a longitudinally arranged waste flue underneath each outer sideportion of said chamber with which the waste port connectionscommunicate; substantially as described.

7. A. furnace of the character described 'having its base provided witha longitudinally extending waste flue adjacent each of its oppositesides, said iiues having ports leading into the side portions of theannealing gas flue, air supply and preheating ingy chamber of the'furnace, and said furnace also having means whereby hot products ofcombustion are caused to pass from the central portion of its annealingchainber toward the opposite side walls thereof,

the base of the furnace having underneath its central portion. alongitudinally extendfines between the gas flue and each of the sideWaste fines, and port connections from said lines for bringing air andgas together at the central portion of the furnace; substantially asdescribed.

8. A furnace of the character described having its base formed with alongitudinal waste port adjacent each side thereof, said fines havingports leading upwardly at the side portions of the annealing chamber ofthe furnace, and said ports having damper means, together with means forthe introduction of the heating medium at the central portion of thefurnace, the dampers providingmeans for independent regulation of thedraft at the two sidesof the furnace; substantially as described.

9. A furnace of the character described having longitudinally extendingvsubstanigrraase tially parallel gas, air and waste iiues Within itsbase, the waste flues having portions adjacent the side walls of thefurnace and communicating with the side portions of the annealingchamber of the furnace, and the air fines having portions which areadjacent to the waste flues, the said gas and ai r lues having portconnections for bringing air and gas together at the central portion ofthe furnace and said chamber being arranged to` permit of a transversepassage of the products of combustion across said chamber from itscentral portion to the sides thereof throughout the major portion of itslength; substantially.7 as described.

10. A furnace of the character described, having a chamber to receivethe material to be heated, said chamber having inlet n'ieans for theheating medium at its central portion and opening directly into saidcliamber, outlet means for the products of coinbustion at each sideportion of said chainber, said chamber having a supporting surface forthe material to be heated between the outlet means at each. side and thecentral inlet means, and being arranged to permit the products ofcombustion to flow transversely across it from the center toward theside in both directions throughout the major portion of its length, andthel base of the furnace below the chaml'ier having longitudinallyarranged gas and air ilues which are connected to the said inlet means.said base also having longitudinally arranged waste flues which areconnected to the said outlets and which has portions which are adjacentto the side walls of the furnace; substantially as described.

1l, A furnace of the character described, having a chamber to receivethe material to be heated, said chaml'ier having inlet means for theheating medium at its central portion and opening directly into saidchamber, outlet means for the products of combustion at each sideportion of said chamber, said chamber having a supporting surface forthe material to be heated between the outlet means at each side and thecentral inlet means` and being arranged to permit the products ofcombustion to flow transversely across it from the center toward theside in both directions throughout the major portion. of its length. thefurnace also having means for supplying preheated air and gas to saidinlet means., and having waste flues communicating with the said outletmeans; substantiallv as described.

ln testimony whereof, I have hereunto set my hand.

JOHN ALBERT SVINDLL. Witnesses Guo. H. PAnMnLiin, H. M'. CoRwiN.

Copies of this patent may be obtained for ve cents each, by addressingthe Commissioner of Patents,

Washington, D. C.

